1. Field of the Invention
The present general inventive concept relates generally to an artifact-processing apparatus. More particularly, the present general inventive concept relates to an apparatus and method of processing shoot artifacts of image signals to reduce the shoot artifacts appearing when the image signals are compressed or pass through bandwidth-limited transmission lines.
2. Description of the Related Art
Artifacts appear due to a reduction of high-frequency components when an image signal goes through lossy compression or bandwidth-limited transmission lines. The artifacts that cause a phenomenon of seemingly overlapped white-colored ripples around edges of the image are called ‘shoot artifacts’.
The shoot artifacts become prominent on the edges of images in which brightness values greatly change as the sharpness of the images having such shoot artifacts is enhanced, and cause the images to appear unnatural.
A conventional scheme for suppressing such shoot artifacts is disclosed in U.S. Pat. No. 6,668,097 B1, the description of which will not be made in detail in here.
In brief, the U.S. Pat. No. 6,668,097 B1 has a problem of no consideration of shoot artifacts appearing on the edges not exceeding a particular threshold value, and suppressing only the shoot artifacts of the edges exceeding the particular threshold value. Furthermore, in regions in which the shoot artifacts are determined to appear, the U.S. Pat. No. 6,668,097 B1 suppresses the shoot artifacts using a ‘gray level opening’ and a ‘gray level closing,’ which causes a problem of truncating components of detailed images.